On Mon, Jun 26, 2023 at 4:05 PM David Marchand <david.march...@redhat.com> wrote: > > On Mon, Jun 26, 2023 at 3:19 PM Ilya Maximets <i.maxim...@ovn.org> wrote: > > > - if the UFO feature is "restored" in the master branch, OVS can't > > > expose CSUM if the guest negotiated UFO. > > > > Yep. IIUC, that will require un-doing/re-wrking some of the changes Mike > > did in order to restore ability to disable advertising of checksum offload. > > We need to disable VIRTIO_NET_F_CSUM (as it was before Mike series) > and make sure ECN and UFO are enabled. > This is the common point for all versions of OVS until now.
- I have been testing a fix, and unfortunately, I can't re-enable UFO through the vhost API. Once disabled in rte_vhost_driver_register(), a feature is removed from the supported features set. rte_vhost_driver_disable_features() does not care about this supported features set, but rte_vhost_driver_enable_features() does. This means that the issue affecting upgrades from 2.11 (because of UFO) can't be fixed from OVS side. Maybe it could be "fixed" with a change on DPDK side, but I am not sure it is worth the risk to preserve a workaround. - Now, pragmatically, this issue on the UFO feature would result in losing connectivity on a vhost-user port. An affected guest would not get a chance to see the newly added VIRTIO_NET_F_CSUM feature. If we can't "fix" UFO advertisement to preserve this workaround on OVS side, there may be nothing to do after Mike series in the end. And my followup patch could be kept as proposed in its v4 form. WDYT? -- David Marchand _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev
